(CNN) -- Tens of thousands of people marched through Chile's capital Thursday, demanding lower tuition and other reforms in the nation's education system.

Police said at least 70,000 people took to the streets in Santiago, CNN Chile reported.

Some protesters hurled stones at authorities as riot police sprayed tear gas and water cannons at demonstrators.

The march drew the attention of Chilean Education Minister Joaquin Lavin.

"The violence worries me. We cannot allow it. The possibility that some children and youth will miss the school year worries me. Every time there are protests, there are stoppages, instead of improving public education, we are hurting it," he said.

"We cannot keep missing classes. Please, I want to call for prudence. On the path we are on, education will not be fixed."

But protest organizers said massive marches were necessary to make the government take notice.

"The education policies must be redesigned," Jaime Gajardo, president of the College of Professors, told CNN Chile. "We cannot continue on this path of privatization."

University students and professors organized the march.

High school students in Chile have also been conducting sit-ins and protests.